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Abstract A novelC3symmetric 1,1’‐bi‐2‐naphthol‐based Schiff base (R,R,R)‐6has been synthesized which shows highly selective fluorescence enhancement with Zn2+among 21 metal cations examined. Its sensitivity and selectivity are found to be greater than other relatedC2(1) andC1[(R)‐9] symmetric compounds in the fluorescent recognition of Zn2+. The mechanistic study reveals that the selective fluorescence enhancement of the probe can be attributed to the formation of a unimolecular multidentate 6‐coordinated Zn2+complex.
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High‐fidelity Recognition of Organotrifluoroborate Anions (R−BF 3 − ) as Designer Guest Molecules
Abstract The recognition of boron compounds is well developed as boronic acids but untapped as organotrifluoroborate anions (R−BF3−). We are exploring the development of these and other designer anions as anion‐recognition motifs by considering them as substituted versions of the parent inorganic ion. To this end, we demonstrate strong and reliable binding of organic trifluoroborates, R−BF3−, by cyanostar macrocycles that are size‐complementary to the inorganic BF4−progenitors. We find that recognition is modulated by the substituent's sterics and that the affinities are retained using the common K+salts of R−BF3−anions.
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- PAR ID:
- 10377258
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 28
- Issue:
- 60
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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